Syria plunging Mideast into sectarian war?

By Peter Bergen and Jennifer Rowland

Updated 1:22 PM ET, Wed September 4, 2013

Photos: Syria's refugee crisis98 photos

Syria's refugee crisis – Syrian refugees board a boat bound for Turkey at a port in Kyrenia, Cyprus, on Sunday, November 23. Some 220 Syrian migrants crammed onto a fishing boat were rescued by a cruise ship off Cyprus' northern coast after their vessel hit rough seas in the Mediterranean Sea, authorities said.

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Syria's refugee crisis – A Syrian Kurdish child looks through the ventilation hole of a tent at a camp in Suruc, Turkey, on Wednesday, November 19. Tens of thousands of people fled the Syrian city of Kobani, alson known as Ayn al-Arab, because of the militant group ISIS.

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Syria's refugee crisis – A fly lands on the toe of 8-year-old Mahmut Munir, a Syrian Kurdish refugee boy from Kobani, inside a tent in Suruc on November 19. The boy was reportedly injured in a mortar attack by ISIS militants.

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Syria's refugee crisis – Kurdish children from the Kobani area speak after receiving food rations at a camp in Suruc on Tuesday, November 18.

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Syria's refugee crisis – A Syrian Kurdish refugee pins a picture of her son on a wall in Suruc on Tuesday, November 11. She says he died during a battle in Kobani.

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Syria's refugee crisis – Syrian Kurdish refugees collect clothes and shoes donated by civilians at a camp in Suruc on November 11.

Syria's refugee crisis – A Syrian Kurdish boy is vaccinated as he arrives in Suruc on September 23. The United Nations estimates that more than 2.5 million Syrians have fled their country since an uprising in March 2011 spiraled into civil war.

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Syria's refugee crisis – A woman carries belongings across the border between Turkey and Syria on September 23.

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Syria's refugee crisis – A Syrian refugee watches the sunrise Wednesday, April 2, after sleeping outside the Center for Temporary Stay of Immigrants in Melilla, Spain.

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Syria's refugee crisis – Mustafa Ahmad, who lost his leg in 2011 when government warplanes bombed his neighborhood in Syria, is fitted with a prosthetic leg at a refugee camp Thursday, March 27, in Jib Janine, Lebanon.

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Syria's refugee crisis – The U.N. Relief and Works Agency for Palestine Refugees in the Near East delivered humanitarian aid packages to the Yarmouk refugee camps in Syria on Friday, March 21.

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Syria's refugee crisis – A boy uses a tool to dig a hole at the Zaatari refugee camp in northern Jordan on Saturday, March 15.

Syria's refugee crisis – After crossing into Jordan's Ruweished camp on Thursday, December 5, a Syrian boy searches for his mother while other refugees board a Jordanian military vehicle.

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Syria's refugee crisis – Newly arrived Syrian refugees carry their belongings and children after crossing into Jordan's Ruweished camp on December 5.

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Syria's refugee crisis – Syrian refugees wait in line to receive winter aid kits at the Zaatari refugee camp near Mafraq, Jordan, on Tuesday, December 3.

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Syria's refugee crisis – Refugees watch a new trailer being placed in the Zaatari camp on December 3.

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Syria's refugee crisis – A Syrian child looks out from his tent at a refugee camp in Arsal on Friday, November 29.

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Syria's refugee crisis – A girl crosses a puddle during the first snowfall of the season in a refugee camp in Harmanli, Bulgaria, on Wednesday, November 27.

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Syria's refugee crisis – Young Syrian refugees play at the recently opened Vrazhdebna shelter in Sofia on Friday, November 22.

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Syria's refugee crisis – Syrian refugees warm themselves near open fires at a refugee camp in Harmanli on Thursday, November 21.

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Syria's refugee crisis – Syrian refugees go about their daily lives in an Istanbul park on Sunday, November 3.

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Syria's refugee crisis – A Syrian refugee uses a rope to climb a tree at the Vrazhdebna shelter on Tuesday, October 29.

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Syria's refugee crisis – Syrian refugees are turned back after being refused entry into northern Iraq on Wednesday, October 23.

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Syria's refugee crisis – Refugees wait to get medical attention at the Vrazhdebna shelter on Saturday, October 19. The shelter is a former school.

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Syria's refugee crisis – A Syrian refugee begs with her children on a street in Beirut, Lebanon, on Friday, October 18.

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Syria's refugee crisis – Kurdish women grieve during a visit to a cemetery in Derik, Syria, on Tuesday, October 15.

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Syria's refugee crisis – Young Syrian refugees from Aleppo sit with their mother on the steps of a Beirut bank in September 2013.

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Syria's refugee crisis – Two Syrian refugees sit on a Beirut street in September 2013.

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Syria's refugee crisis – Young Syrian refugees sit with their father as he prepares coffee to sell on a street in Beirut in September 2013.

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Syria's refugee crisis – A Syrian refugee boy practices taekwondo at the Zaatari refugee camp near Mafraq in September 2013.

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Syria's refugee crisis – A young Syrian girl washes a pan at the Atme refugee camp along the Turkish border in September 2013.

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Syria's refugee crisis – Syrian refugee children watch Korean and Syrian taekwondo instructors during training at the Zaatari refugee camp in Jordan in September 2013.

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Syria's refugee crisis – A Syrian woman carries her baby across the border into Turkey at the Cilvegozu border gate in September 2013.

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Syria's refugee crisis – A Syrian girl stands with her mother in a makeshift tent as they wait to enter an official refugee camp at the Oncupinar border gate in Kilis, Turkey, in September 2013.

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Syria's refugee crisis – A Syrian girl eats a tomato at a temporary refugee camp in the eastern Lebanese town of al-Faour in September 2013.

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Syria's refugee crisis – A Syrian refugee girl drinks water from a hose near a temporary refugee camp in an eastern Lebanese town in September 2013.

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Syria's refugee crisis – In September 2013, Lower Saxony's Commissioner for Migration and Participation Doris Schroeder-Koempf, along with German Interior Minister Hans-Peter Friedrich, center, greet the first of many Syrian refugees that have been granted temporary asylum in Germany.

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Syria's refugee crisis – A refugee boy sits on the ground at a temporary refugee camp in the eastern Lebanese town of al-Faour in September 2013.

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Syria's refugee crisis – Syrian refugee children run near their tents at a temporary refugee camp near the Lebanese border in September 2013.

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Syria's refugee crisis – Mustafa Abu Bekir, who was wounded while fighting with the Free Syrian Army, smiles as he meets relatives after crossing the Cilvegozu gate border in Turkey's Hatay province in September 2013.

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Syria's refugee crisis – A Syrian refugee family of 26 people shares one room in the Eminonu district of Istanbul in September 2013.

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Syria's refugee crisis – Two Syrian refugee children sit outside a house in Istanbul in September 2013.

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Syria's refugee crisis – A refugee money-changer exchanges currency at the main market at the Zaatari refugee camp near Mafraq in September 2013.

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Syria's refugee crisis – A woman from an Alawite neighborhood in Syria holds her son in September 2013 at the Pir Sultan Abdal foundation in Istanbul.

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Syria's refugee crisis – A Syrian refugee displays second-hand shoes for sale at the main market at the Zaatari refugee camp near Mafraq in September 2013.

Story highlights

He says the historic Sunni-Shia split is a key dynamic and U.S. strike could worsen conflict

Iraq's death toll from sectarian struggles has been increasing

Bergen: Al Qaeda-affiliated groups will seek to take advantage

As they contemplate military action against Syria, one of many considerations members of Congress and Obama administration officials have to weigh is how a U.S. strike against the regime of Bashar al-Assad might effect the already complicated, even poisonous, state of Sunni-Shia relations in the region.

Three of the leading Sunni states, Saudi Arabia, Turkey and the UAE, have already offered their military assets if a US strike happens.

Last week, Iranian President Hassan Rouhani said that the Shia government of Iran and close Syrian ally Russia would work in "extensive cooperation" to protect Syria.

An American-led war in Syria with the military backing of some powerful Sunni states against a de facto Shia alliance of Iran, Syria, Iraq and Lebanese Hezbollah would likely greatly exacerbate the already tense relations between Sunni and Shia across the region.

Peter Bergen

In Syria, a popular uprising against a repressive ruler in 2011 has morphed into what is now a largely sectarian civil war pitting the country's Sunni Muslim majority against al-Assad's minority Alawite sect, which is associated with Shia Islam.

The Syrian regime is propped up with weapons and funds from Iran's Shia rulers and also benefits significantly from the support on the ground of battle-hardened fighters from Lebanese Hezbollah, an Iranian proxy.

As a possible U.S. strike looms in Syria, what had hitherto been a shadowy proxy war, with Sunni countries such as Saudi Arabia quietly supporting the Syrian rebels and Iran supporting al-Assad, could now devolve into a full-blown war that is openly supported by the most powerful Sunni and Shia states.

That is a real potential problem that needs to be weighed by Obama national security officials and representatives in Congress as they consider the options in Syria, because across the Muslim world from Lebanon to Pakistan, Sunnis and Shias are increasingly at each other's throats.

A further intensification of the already brutal Syrian civil war might further destabilize Syria's fragile neighbors; both Lebanon and Iraq could plunge back into civil wars.

Already in July, the United Nations recorded the highest death toll in Iraq since 2008, when the Iraq War was raging. In that month alone, more than 1,057 civilians and security personnel were killed. Many of those deaths were the result of bombings claimed by the Sunni terrorist group al-Qaeda in Iraq and were directed at Shia targets.

Obama: 'I didn't set a red line'

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Why are Iraq's Sunnis so upset?

A splinter organization of al-Qaeda in Iraq is now fighting in Syria and is regarded as the most effective force fighting Assad, who it deems a heretic.

It's a very old story. The two dominant sects of Islam, Sunni and Shia, first split over the issue of who was the rightful successor of the Prophet Muhammad following his death in 632.

The conflict between the two sects has waxed and waned over the many centuries since, but right now the Syrian conflict could exacerbate the regional split along sectarian lines that we have seen over the past few years.

In 2011 the Sunni monarchy of the Gulf state of Bahrain backed by more than a thousand soldiers from Saudi Arabia put down with harsh tactics an uprising by its disadvantaged Shia majority population. The Bahrain government hinted that the uprising was an Iranian plot.

The sectarian conflicts in Syria, Iraq and Bahrain have also spilled over into Lebanon and Egypt. On June 23, in Lebanon's port city of Sidon, soldiers clashed with supporters of a hardline Sunni cleric, Sheikh Ahmed al-Assir, who had spoken out vehemently against the Syrian regime as well as the Shia Lebanese militant group, Hezbollah.

On the same day, four Egyptian Shia Muslims were stabbed, beaten, and dragged through the streets by members of a hardline Sunni group in the Giza neighborhood of Cairo.

The intensifying sectarian tensions in Egypt were partially the fault of the recently-ousted Muslim Brotherhood government. A week before the Giza attack, for example, President Mohamed Morsi had appeared on stage with hardline clerics who called Shias "filthy." And in May, Salafist members of Egypt's parliament denounced Shias as "a danger to Egypt's national security."

Beyond the Middle East, sectarian violence has also soared in South Asia over the past few years. More than 180 members of Pakistan's minority Shi'a Hazara community were killed in two massive bombings in the first two months of 2013 alone.

In neighboring Afghanistan, violent attacks on Shia Muslims are less frequent, but in December 2011, two nearly simultaneous suicide bombs in Kabul and Mazar-i-Sharif killed more than 60 Shia civilians as they celebrated the annual religious festival of Ashura.

We can expect sectarian tensions to continue boiling across the Muslim world, as the Syrian conflict grinds on and political and social unrest persist in many countries in the region.

Al-Qaeda-affiliated groups will seek to exploit these sectarian divisions to garner support for their own violent agenda, and may well find greater room to operate because of it.

Saudi Arabia and Qatar have mobilized their deep coffers to support extremist Sunni groups in the past, and will continue to do so as long as it means they are able to counterbalance Iran and its support for Shia regimes and militant groups.

All of these factors must be weighed as the United States weighs military action. They are not an argument for doing nothing in the face of al-Assad's large-scale use of chemical weapons but they are a reason to heed Machiavelli's warning "Wars begin when you will, but they do not end when you please."